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Design,progress and challenges of 3D carbon-based thermally conductive networks 被引量:2
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作者 JING Yuan LIU Han-qing +2 位作者 ZHOU Feng DAI Fang-na WU Zhong-shuai 《新型炭材料(中英文)》 SCIE EI CAS CSCD 北大核心 2024年第5期844-871,共28页
The advent of the 5G era has stimulated the rapid development of high power electronics with dense integration.Three-dimensional(3D)thermally conductive networks,possessing high thermal and electrical conductivities a... The advent of the 5G era has stimulated the rapid development of high power electronics with dense integration.Three-dimensional(3D)thermally conductive networks,possessing high thermal and electrical conductivities and many different structures,are regarded as key materials to improve the performance of electronic devices.We provide a critical overview of carbonbased 3D thermally conductive networks,emphasizing their preparation-structure-property relationships and their applications in different scenarios.A detailed discussion of the microscopic principles of thermal conductivity is provided,which is crucial for increasing it.This is followed by an in-depth account of the construction of 3D networks using different carbon materials,such as graphene,carbon foam,and carbon nanotubes.Techniques for the assembly of two-dimensional graphene into 3D networks and their effects on thermal conductivity are emphasized.Finally,the existing challenges and future prospects for 3D carbon-based thermally conductive networks are discussed. 展开更多
关键词 Carbon material 3d network GRAPHENE Thermal conductivity Heat transfer
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A review of 3D graphene materials for energy storage and conversion
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作者 WU Zi-yuan XU Chi-wei +2 位作者 ZENG Jin-jue JIANG Xiang-fen WANG Xue-bin 《新型炭材料(中英文)》 北大核心 2025年第3期477-518,共42页
Three-dimensional(3D)graphene monoliths are a new carbon material,that has tremendous potential in the fields of energy conversion and storage.They can solve the limitations of two-dimensional(2D)graphene sheets,inclu... Three-dimensional(3D)graphene monoliths are a new carbon material,that has tremendous potential in the fields of energy conversion and storage.They can solve the limitations of two-dimensional(2D)graphene sheets,including interlayer restacking,high contact resistance,and insufficient pore accessibility.By constructing interconnected porous networks,3D graphenes not only retain the intrinsic advantages of 2D graphene sheets,such as high specific surface area,excellent electrical and thermal conductivities,good mechanical properties,and outstanding chemical stability,but also enable efficient mass transport of external fluid species.We summarize the fabrication methods for 3D graphenes,with a particular focus on their applications in energy-related systems.Techniques including chemical reduction assembly,chemical vapor deposition,3D printing,chemical blowing,and zinc-tiered pyrolysis have been developed to change their pore structure and elemental composition,and ways in which they can be integrated with functional components.In terms of energy conversion and storage,they have found broad use in buffering mechanical impacts,suppressing noise,photothermal conversion,electromagnetic shielding and absorption.They have also been used in electrochemical energy systems such as supercapacitors,secondary batteries,and electrocatalysis.By reviewing recent progress in structural design and new applications,we also discuss the problems these materials face,including scalable fabrication and precise pore structure control,and possible new applications. 展开更多
关键词 GRAPHENE 3d network SYNTHESIS Energy storage Energy conversion
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AUV 3D path planning based on improved PSO
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作者 LI Hongen LI Shilong +1 位作者 WANG Qi HUANG Xiaoming 《Journal of Systems Engineering and Electronics》 2025年第3期854-866,共13页
The influence of ocean environment on navigation of autonomous underwater vehicle(AUV)cannot be ignored.In the marine environment,ocean currents,internal waves,and obstacles are usually considered in AUV path planning... The influence of ocean environment on navigation of autonomous underwater vehicle(AUV)cannot be ignored.In the marine environment,ocean currents,internal waves,and obstacles are usually considered in AUV path planning.In this paper,an improved particle swarm optimization(PSO)is proposed to solve three problems,traditional PSO algorithm is prone to fall into local optimization,path smoothing is always carried out after all the path planning steps,and the path fitness function is so simple that it cannot adapt to complex marine environment.The adaptive inertia weight and the“active”particle of the fish swarm algorithm are established to improve the global search and local search ability of the algorithm.The cubic spline interpolation method is combined with PSO to smooth the path in real time.The fitness function of the algorithm is optimized.Five evaluation indexes are comprehensively considered to solve the three-demensional(3D)path planning problem of AUV in the ocean currents and internal wave environment.The proposed method improves the safety of the path planning and saves energy. 展开更多
关键词 autonomous underwater vehicle(AUV) three-dimensional(3d)path planning particle swarm optimization(PSO) cubic spline interpolation
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Three-dimensional multi-constraint route planning of unmanned aerial vehicle low-altitude penetration based on coevolutionary multi-agent genetic algorithm 被引量:8
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作者 彭志红 吴金平 陈杰 《Journal of Central South University》 SCIE EI CAS 2011年第5期1502-1508,共7页
To address the issue of premature convergence and slow convergence rate in three-dimensional (3D) route planning of unmanned aerial vehicle (UAV) low-altitude penetration,a novel route planning method was proposed.Fir... To address the issue of premature convergence and slow convergence rate in three-dimensional (3D) route planning of unmanned aerial vehicle (UAV) low-altitude penetration,a novel route planning method was proposed.First and foremost,a coevolutionary multi-agent genetic algorithm (CE-MAGA) was formed by introducing coevolutionary mechanism to multi-agent genetic algorithm (MAGA),an efficient global optimization algorithm.A dynamic route representation form was also adopted to improve the flight route accuracy.Moreover,an efficient constraint handling method was used to simplify the treatment of multi-constraint and reduce the time-cost of planning computation.Simulation and corresponding analysis show that the planning results of CE-MAGA have better performance on terrain following,terrain avoidance,threat avoidance (TF/TA2) and lower route costs than other existing algorithms.In addition,feasible flight routes can be acquired within 2 s,and the convergence rate of the whole evolutionary process is very fast. 展开更多
关键词 unmanned aerial vehicle (UAV) low-altitude penetration three-dimensional (3d) route planning coevolutionary multiagent genetic algorithm (CE-MAGA)
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SAR regional all-azimuth observation orbit design for target 3D reconstruction
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作者 WANG Yanan ZHOU Chaowei +1 位作者 LIU Aifang MAO Qin 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第3期609-618,共10页
Three-dimensional(3D) synthetic aperture radar(SAR)extends the conventional 2D images into 3D features by several acquisitions in different aspects. Compared with 3D techniques via multiple observations in elevation, ... Three-dimensional(3D) synthetic aperture radar(SAR)extends the conventional 2D images into 3D features by several acquisitions in different aspects. Compared with 3D techniques via multiple observations in elevation, e.g. SAR interferometry(InSAR) and SAR tomography(TomoSAR), holographic SAR can retrieve 3D structure by observations in azimuth. This paper focuses on designing a novel type of orbit to achieve SAR regional all-azimuth observation(AAO) for embedded targets detection and holographic 3D reconstruction. The ground tracks of the AAO orbit separate the earth surface into grids. Target in these grids can be accessed with an azimuth angle span of360°, which is similar to the flight path of airborne circular SAR(CSAR). Inspired from the successive coverage orbits of optical sensors, several optimizations are made in the proposed method to ensure favorable grazing angles, the performance of 3D reconstruction, and long-term supervision for SAR sensors. Simulation experiments show the regional AAO can be completed within five hours. In addition, a second AAO of the same area can be duplicated in two days. Finally, an airborne SAR data process result is presented to illustrate the significance of AAO in 3D reconstruction. 展开更多
关键词 synthetic aperture radar(SAR) orbit design all-azimuth observation(AAO) three-dimensional(3d)reconstruction successive coverage
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Research on BIM Model Reshaping Method Based on 3D Point Cloud Recognition
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作者 SHI Jin-yu YU Xian-feng +1 位作者 SI Zhan-jun ZHANG Ying-xue 《印刷与数字媒体技术研究》 CAS 北大核心 2024年第4期125-135,共11页
In view of the limitations of traditional measurement methods in the field of building information,such as complex operation,low timeliness and poor accuracy,a new way of combining three-dimensional scanning technolog... In view of the limitations of traditional measurement methods in the field of building information,such as complex operation,low timeliness and poor accuracy,a new way of combining three-dimensional scanning technology and BIM(Building Information Modeling)model was discussed.Focused on the efficient acquisition of building geometric information using the fast-developing 3D point cloud technology,an improved deep learning-based 3D point cloud recognition method was proposed.The method optimised the network structure based on RandLA-Net to adapt to the large-scale point cloud processing requirements,while the semantic and instance features of the point cloud were integrated to significantly improve the recognition accuracy and provide a precise basis for BIM model remodeling.In addition,a visual BIM model generation system was developed,which systematically transformed the point cloud recognition results into BIM component parameters,automatically constructed BIM models,and promoted the open sharing and secondary development of models.The research results not only effectively promote the automation process of converting 3D point cloud data to refined BIM models,but also provide important technical support for promoting building informatisation and accelerating the construction of smart cities,showing a wide range of application potential and practical value. 展开更多
关键词 3d point cloud RandLA-Net network BIM model OSG engine
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Probabilistic analysis on fault tolerance of 3-Dimensional mesh networks
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作者 王高才 陈建二 +1 位作者 王国军 陈松乔 《Journal of Central South University of Technology》 2003年第3期255-259,共5页
The probability model is used to analyze the fault tolerance of mesh. To simplify its analysis, it is as-sumed that the failure probability of each node is independent. A 3-D mesh is partitioned into smaller submeshes... The probability model is used to analyze the fault tolerance of mesh. To simplify its analysis, it is as-sumed that the failure probability of each node is independent. A 3-D mesh is partitioned into smaller submeshes,and then the probability with which each submesh satisfies the defined condition is computed. If each submesh satis-fies the condition, then the whole mesh is connected. Consequently, the probability that a 3-D mesh is connected iscomputed assuming each node has a failure probability. Mathematical methods are used to derive a relationship be-tween network node failure probability and network connectivity probability. The calculated results show that the 3-D mesh networks can remain connected with very high probability in practice. It is formally proved that when thenetwork node failure probability is boutded by 0.45 %, the 3-D mesh networks of more than three hundred thousandnodes remain connected with probability larger than 99 %. The theoretical results show that the method is a power-ful technique to calculate the lower bound of the connectivity probability of mesh networks. 展开更多
关键词 3-d MESH networkS k-submesh CONNECTIVITY PROBABILITY analysis
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在3D-Mesh网络中的两种路由研究 被引量:4
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作者 肖杰 梁家荣 +1 位作者 徐霜 李银 《计算机工程与应用》 CSCD 北大核心 2008年第17期90-93,共4页
在研究并行计算机系统容错时,路由算法是一个极为重要的研究课题。主要研究的是自适应路由算法和确定性路由算法在3D-Mesh网络上的性能。在每个结点具有独立的出错概率的模型下,提出的方法使得能够严格地推导出路由算法的成功概率,从而... 在研究并行计算机系统容错时,路由算法是一个极为重要的研究课题。主要研究的是自适应路由算法和确定性路由算法在3D-Mesh网络上的性能。在每个结点具有独立的出错概率的模型下,提出的方法使得能够严格地推导出路由算法的成功概率,从而能够对算法进行分析和比较。研究结果表明,自适应路由算法具有明显的优势。一方面,自适应路由算法基于局部信息而变得高效;另一方面,自适应路由算法对于结点出错和网络规模具有更好的健壮性,而使其具有更高的成功概率。 展开更多
关键词 确定性路由算法 自适应路由算法 网络容错 3d—Mesh网络
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基于3D-Tabu禁忌搜索的广域环境MESH网络节点部署优化算法研究 被引量:7
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作者 王鸿鹏 王前 +2 位作者 张晓阳 何明 陈海华 《传感技术学报》 CAS CSCD 北大核心 2021年第2期261-267,共7页
受限于广域环境的特殊三维地形及其大覆盖面积,需要一个能够基于三维地理广域场景的节点智能化部署方案。本文结合WiFi MESH网络、动态组网算法等知识,基于广域三维山区环境,提炼出数学模型,并运用MESH网络和启发式搜索算法的思想,在满... 受限于广域环境的特殊三维地形及其大覆盖面积,需要一个能够基于三维地理广域场景的节点智能化部署方案。本文结合WiFi MESH网络、动态组网算法等知识,基于广域三维山区环境,提炼出数学模型,并运用MESH网络和启发式搜索算法的思想,在满足最小建设成本、最大覆盖率以及最优网络服务质量三个限制条件综合最优的前提下,提出了一种基于三维禁忌搜索算法的多目标优化节点部署方法。此外,还提出了一种可以针对不同应用场景的"加权求和"综合评价机制。仿真实验结果表明,提出的三维禁忌搜索算法可有效获得满足约束条件的优化部署方案;通过对加权系数的分析验证了评价机制的科学优化程度。此外,本文提出的搜索算法可以根据不同的应用场景获得一个最优化的智能基站部署方案,推动了智能基站自动部署规划在广域场景中的应用。 展开更多
关键词 MESH网络 广域三维环境 禁忌搜索算法 节点部署
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Quantitative determination of PFC3D microscopic parameters 被引量:7
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作者 LI Zhuo RAO Qiu-hua 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第3期911-925,共15页
It is important to calibrate micro-parameters for applying partied flow code(PFC)to study mechanical characteristics and failure mechanism of rock materials.Uniform design method is firstly adopted to determine the mi... It is important to calibrate micro-parameters for applying partied flow code(PFC)to study mechanical characteristics and failure mechanism of rock materials.Uniform design method is firstly adopted to determine the microscopic parameters of parallel-bonded particle model for three-dimensional discrete element particle flow code(PFC3D).Variation ranges of microscopic of the microscopic parameters are created by analyzing the effects of microscopic parameters on macroscopic parameters(elastic modulus E,Poisson ratio v,uniaxial compressive strengthσc,and ratio of crack initial stress to uniaxial compressive strengthσci/σc)in order to obtain the actual uniform design talbe.The calculation equations of the microscopic and macroscopic parameters of rock materials can be established by the actual uniform design table and the regression analysis and thus the PFC3D microscopic parameters can be quantitatively determined.The PFC3D simulated results of the intact and pre-cracked rock specimens under uniaxial and triaxial compressions(including the macroscopic mechanical parameters,stress−strain curves and failure process)are in good agreement with experimental results,which can prove the validity of the calculation equations of microscopic and macroscopic parameters. 展开更多
关键词 quantitative relationship of microscopic and macroscopic parameters uniform design method three-dimensional particle flow code(PFC3d) ROCK
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Monopulse instantaneous 3D imaging for wideband radar system 被引量:3
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作者 LI Yuhan QI Wei +2 位作者 DENG Zhenmiao FU Maozhong ZHANG Yunjian 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第1期53-67,共15页
To avoid the complicated motion compensation in interferometric inverse synthetic aperture(InISAR)and achieve realtime three-dimensional(3 D)imaging,a novel approach for 3 D imaging of the target only using a single e... To avoid the complicated motion compensation in interferometric inverse synthetic aperture(InISAR)and achieve realtime three-dimensional(3 D)imaging,a novel approach for 3 D imaging of the target only using a single echo is presented.This method is based on an isolated scatterer model assumption,thus the scatterers in the beam can be extracted individually.The radial range of each scatterer is estimated by the maximal likelihood estimation.Then,the horizontal and vertical wave path difference is derived by using the phase comparison technology for each scatterer,respectively.Finally,by utilizing the relationship among the 3 D coordinates,the radial range,the horizontal and vertical wave path difference,the 3 D image of the target can be reconstructed.The reconstructed image is free from the limitation in InISAR that the image plane depends on the target's own motions and on its relative position with respect to the radar.Furthermore,a phase ambiguity resolution method is adopted to ensure the success of the 3 D imaging when phase ambiguity occurs.It can be noted that the proposed phase ambiguity resolution method only uses one antenna pair and does not require a priori knowledge,whereas the existing phase ambiguity methods may require two or more antenna pairs or a priori knowledge for phase unwarping.To evaluate the performance of the proposed method,the theoretical analyses on estimation accuracy are presented and the simulations in various scenarios are also carried out. 展开更多
关键词 cross-correlation operation phase ambiguity resolution wave path difference estimation monopulse three-dimensional(3d)imaging
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Airborne sparse flight array SAR 3D imaging based on compressed sensing in frequency domain 被引量:2
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作者 TIAN He DONG Chunzhu +1 位作者 YIN Hongcheng YUAN Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第1期56-67,共12页
In airborne array synthetic aperture radar(SAR), the three-dimensional(3D) imaging performance and cross-track resolution depends on the length of the equivalent array. In this paper, Barker sequence criterion is used... In airborne array synthetic aperture radar(SAR), the three-dimensional(3D) imaging performance and cross-track resolution depends on the length of the equivalent array. In this paper, Barker sequence criterion is used for sparse flight sampling of airborne array SAR, in order to obtain high cross-track resolution in as few times of flights as possible. Under each flight, the imaging algorithm of back projection(BP) and the data extraction method based on modified uniformly redundant arrays(MURAs) are utilized to obtain complex 3D image pairs. To solve the side-lobe noise in images, the interferometry between each image pair is implemented, and compressed sensing(CS) reconstruction is adopted in the frequency domain. Furthermore, to restore the geometrical relationship between each flight, the phase information corresponding to negative MURA is compensated on each single-pass image reconstructed by CS. Finally,by coherent accumulation of each complex image, the high resolution in cross-track direction is obtained. Simulations and experiments in X-band verify the availability. 展开更多
关键词 three-dimensional(3d)imaging synthetic aperture radar(SAR) sparse flight INTERFEROMETRY compressed sensing(CS)
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3D Integrated Geological Modeling in Tongshan Copper Deposit,Heilongjiang Province,China
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作者 Gongwen Wang,Limei Wang,Ge Cui,Chengyin Tan,Shanyan Jin School of Earth Sciences and Resources,China University of Geosciences(Beijing),Beijing 100083,China. 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期282-283,共2页
In this paper,3D-GIS reconstruction and interpolation approach,additional virtual borehole technology and BP network technology are used to explore the concealed ore body.The virtual borehole has same function as real... In this paper,3D-GIS reconstruction and interpolation approach,additional virtual borehole technology and BP network technology are used to explore the concealed ore body.The virtual borehole has same function as reality borehole due to the multi-information check and validation in 展开更多
关键词 3d GEOLOGICAL modeling virtual BOREHOLE BP network MINERAL EXPLORATION Tongshan copper dEPOSIT
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Autonomous UAV 3D trajectory optimization and transmission scheduling for sensor data collection on uneven terrains
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作者 Andrey V.Savkin Satish C.Verma Wei Ni 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第12期154-160,共7页
This paper considers a time-constrained data collection problem from a network of ground sensors located on uneven terrain by an Unmanned Aerial Vehicle(UAV),a typical Unmanned Aerial System(UAS).The ground sensors ha... This paper considers a time-constrained data collection problem from a network of ground sensors located on uneven terrain by an Unmanned Aerial Vehicle(UAV),a typical Unmanned Aerial System(UAS).The ground sensors harvest renewable energy and are equipped with batteries and data buffers.The ground sensor model takes into account sensor data buffer and battery limitations.An asymptotically globally optimal method of joint UAV 3D trajectory optimization and data transmission schedule is developed.The developed method maximizes the amount of data transmitted to the UAV without losses and too long delays and minimizes the propulsion energy of the UAV.The developed algorithm of optimal trajectory optimization and transmission scheduling is based on dynamic programming.Computer simulations demonstrate the effectiveness of the proposed algorithm. 展开更多
关键词 Unmanned aerial system UAS Unmanned aerial vehicle UAV Wireless sensor networks UAS-Assisted data collection 3d trajectory optimization data transmission scheduling
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广义RQD在岩体各向异性中的应用研究 被引量:2
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作者 王国欣 王旭东 肖树芳 《吉林大学学报(地球科学版)》 EI CAS CSCD 北大核心 2002年第3期258-260,共3页
RQD作为工程实际中评价岩体性质的方法 ,应用已相当广泛 ,并已列入有关规范 ,然而由于传统Deere定义的RQD在实际应用中存在很多问题 ,所以引入了不同阈值下的广义RQD的概念 ,并结合不连续面三维网络模拟技术判定岩体的各向异性程度。在... RQD作为工程实际中评价岩体性质的方法 ,应用已相当广泛 ,并已列入有关规范 ,然而由于传统Deere定义的RQD在实际应用中存在很多问题 ,所以引入了不同阈值下的广义RQD的概念 ,并结合不连续面三维网络模拟技术判定岩体的各向异性程度。在对长白公路石碑岭隧道围岩的稳定性评价中 。 展开更多
关键词 RQd 各向异性 三维网络 围岩 稳定性 隧道
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超分子三维氢键网络:{[Cu(phen)_3](SO_4)(H_3PCA)_2(8H_2O)}的晶体结构 被引量:3
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作者 何洪银 朱龙观 《无机化学学报》 SCIE CAS CSCD 北大核心 2003年第3期317-320,共4页
A new complex,{[Cu(phen) 3 ](SO 4 )(H 3 PCA) 2 (8H 2 O)},was synthesized and structurally c haracterized by single-crystal X-ray analysis.The complex is composed of copper cation s,sulfate anions,1,10-phenanthro lin... A new complex,{[Cu(phen) 3 ](SO 4 )(H 3 PCA) 2 (8H 2 O)},was synthesized and structurally c haracterized by single-crystal X-ray analysis.The complex is composed of copper cation s,sulfate anions,1,10-phenanthro line,protocatechuic acid and lattice water molecules.The structure of H 3 PCA,SO 42- and waters comprises packing of anionic three-dimensional network by hydrogen bonds with cavities.The complex can be considered as a model o f host /guest supramolecule.The thre e-dimensional hydrogen-bonding network is the host species.The Cu(phen) 32+ cations,guest species,occupied th e cavities of the host.And the results demonstrate that the form of protocatechuic acid at pH <1should be free ligand.CC DC:191733. 展开更多
关键词 二维网络 三维网络 超分子 氢键 晶体结构
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服装CAD技术发展与展望 被引量:17
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作者 赵锘平 张渭源 张鸿志 《天津纺织工学院学报》 北大核心 2000年第5期70-73,共4页
在回顾服装 CAD技术发展历程的基础上 ,对今后的发展趋势进行了展望 .研究认为 ,服装 CAD发展方向在于三维服装 CAD技术和智能服装 CAD系统 ,它将与 CIMS和网络结合促动服装行业新的发展 .
关键词 服装CAd 三维造地智能系统 CIMS 网络化
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三维移动Ad hoc网络链路动态性研究 被引量:3
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作者 郑博 黄国策 张衡阳 《电子与信息学报》 EI CSCD 北大核心 2011年第11期2605-2609,共5页
3维移动Ad hoc网络(3-D MANET)是一种网络场景分布于3维空间的移动Ad hoc网络。链路动态性分析是研究3-D MANET的一项基础性工作,其结论可作为网络协议设计的基础。该文基于CV(Constant Velocity)移动模型,从概率模型的角度推导出了链... 3维移动Ad hoc网络(3-D MANET)是一种网络场景分布于3维空间的移动Ad hoc网络。链路动态性分析是研究3-D MANET的一项基础性工作,其结论可作为网络协议设计的基础。该文基于CV(Constant Velocity)移动模型,从概率模型的角度推导出了链路寿命期望和分布的数学表达式,并通过仿真实验进行了验证,表明了理论计算结果的正确性。结论对3-D MANET的研究和应用具有一定的参考价值。 展开更多
关键词 3维移动Ad HOC网络 链路动态性 链路寿命 期望 概率密度函数
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基于注意力-残差双特征流卷积神经网络的深度图帧内编码单元快速划分算法
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作者 贾克斌 吴岳珩 《北京工业大学学报》 北大核心 2025年第5期539-551,共13页
针对三维高效视频编码(three-dimensional high efficiency video coding,3D-HEVC)深度图编码单元(coding unit,CU)划分复杂度高的问题,提出一种基于卷积神经网络(convolutional neural networks,CNN)的算法来实现快速深度图帧内编码。... 针对三维高效视频编码(three-dimensional high efficiency video coding,3D-HEVC)深度图编码单元(coding unit,CU)划分复杂度高的问题,提出一种基于卷积神经网络(convolutional neural networks,CNN)的算法来实现快速深度图帧内编码。首先,提出一种具有3个分支的注意力-残差双特征流卷积神经网络(attention-residual bi-feature stream convolutional neural networks,ARBS-CNN)模型,其中基于残差模块(residual module,RM)和特征蒸馏(feature distill,FD)模块的2个分支用于提取全局图像特征,基于动态模块(dynamic module,DM)和卷积-卷积块注意力模块(convolutional-convolutional block attention module,Conv-CBAM)的分支用于提取局部图像特征;然后,将提取到的特征进行整合并输出,得到对深度图CU划分结构的预测;最后,将ARBS-CNN嵌入到3D-HEVC测试平台中,利用预测结果加速深度图帧内编码。与原始算法相比,提出的算法能在维持率失真性能几乎不受影响的条件下,平均减少74.2%的编码时间。实验结果表明,该算法能够在保持率失真性能的条件下,有效降低3D-HEVC的编码复杂度。 展开更多
关键词 三维高效视频编码(three-dimensional high efficiency video coding 3d-HEVC) 深度图 卷积神经网络(convolutional neural networks CNN) 编码单元(coding unit CU)划分 帧内编码 双特征流
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BTDGCNN:面向三维点云拓扑结构的BallTree动态图卷积神经网络 被引量:4
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作者 张学典 方慧 《小型微型计算机系统》 CSCD 北大核心 2022年第11期2342-2347,共6页
点云卷积网络对点云进行分割分类时,独立提取点云特征却忽略了点之间的几何关联,从而丢失了许多局部特征.而对稀疏、无结构、无序的点云进行输入转换则会导致数据变得更加庞大,卷积效率降低.为此构建了面向三维点云拓扑结构的BallTree... 点云卷积网络对点云进行分割分类时,独立提取点云特征却忽略了点之间的几何关联,从而丢失了许多局部特征.而对稀疏、无结构、无序的点云进行输入转换则会导致数据变得更加庞大,卷积效率降低.为此构建了面向三维点云拓扑结构的BallTree动态图卷积神经网络,利用Bat-Net变换网络(BallTree transfromation network)对初始无序点云进行空间变换,恢复点云的拓扑结构和距离向量,提高点云中各个点间的关联性,结合三层BAT边卷积模块(BallTree edge convolution network),提升其信息表征能力,以便更好地进行分类分割任务.实验结果表明,该方法在ModelNet40数据集上的分类性能均优于其他五种方法,分别提高了4.4%、2.9%、1.3%、2%和1.4%.同时在ShapeNet Parts数据集上的分割的平均交并比分别提高了1.7%、0.3%、0.3%、0.3%、0.3%,有效地提升了三维点云的分类分割性能. 展开更多
关键词 三维点云 图卷积神经网络 分类 分割
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